Although this shows to me how badly Lucky is stunted and potentially (at least I think) a runt too. 1 year old fish measuring 5 inches? She's probably more than a year old and very much behind on that XD (although she is nearly 4 inches now!).

Yeah, I'm wondering what other elements could have affected her you know? She was only in that little tank for 6 months But then again I suppose 6 months as a juvenile, is more damaging, than 6 months in a small tank for an older fish.

I'm convinced she must be a runt and can only imagine what the conditions for her were like before! I am going to get a larger home for her once she reaches 6 inches (using the 6x fish size stocking rule with the tank, so being 3 foot = 6 inches is the max size), but right now that looks like it's going to take a few years

Hmmm that's a good question Scrivens, I honestly don't know if it was congenital as I never saw Lucky when she was born or in the first few months of her life. She had the fin when I first got her over a year ago, so I can only assume yes?

I don't think a fish could have survived such an injury at such a young age could it?